swlabhot

I'm building my B18C6 soon and what I like to know is if I put in 9:1 or 9.5 comp pistons in what would be the effective compression if the head gasket is oem? The stock compression right now is 11:0 on stock block.

Another thing, what compression do the JE's come in?

MiraiZ

the piston compression number is usually calculated using stock block, head, and gasket...so to answer your question, 9:1 would be 9:1 and 9.5 is 9.5...if you use stock thickness and you should be ok

swlabhot

So if I use 9:5 pistons I can further bring the compression down with a thicker head gasket right? How does the thickness of the gasket ratio relate to the drop/increase in comp (i.e 0.5mm thicker equates to -1 drop in comp)?

Anyone knows the comp that the JEs come in?

TIA

swlabhot

The JEs come in 9:1 and 12.5:1 if I'm not mistaken....?